Field of the Invention
The present invention relates to a pattern-forming method and a composition for resist pattern-refinement.
Discussion of the Background
Miniaturization of structures of various types of electronic devices such as semiconductor devices and liquid crystal devices has been accompanied by demands for microfabrication of patterns in lithography processes. To address such demands, a method of forming a pattern by exposing and developing a resist film formed using a resist composition containing a radiation-sensitive acid generator and a polymer having a solubility in a developer solution that will be altered by the action of an acid, and additionally a method in which further refining is attempted based on the pattern thus formed have been studied.
Such a method is exemplified by a known technique which includes subjecting a formed pattern (prepattern) to an action of a crosslinking layer-forming material, thereby permitting crosslinkage of the crosslinking layer-forming material with a resin constituting the pattern to form a crosslinking layer (see Japanese Unexamined Patent Application, Publication No. 2008-310314). Further, a technique which includes: applying a coating-forming agent on a resist pattern; then heating to form a layer that is hardly soluble in a developer solution without being accompanied by an increase in the molecular weight on the surface of the resist pattern, so as to increase the thickness of the pattern has been studied (see Japanese Unexamined Patent Application, Publication No. 2013-117710). Furthermore, a technique of increasing the thickness of a pattern by forming a film on a negative pattern using a composition containing a compound having a solubility in a removing liquid containing an organic solvent that will be increased by the action of an acid through an increase in the polarity has been studied (see Japanese Unexamined Patent Application, Publication No. 2013-257435).